-LRB- CNN -RRB- -- Since the start of the financial crisis , the world 's wealthiest man , investor Warren Buffett , has been front and center .

Alice Schroeder says investor Warren Buffett has become a symbol of stability in American business .

He 's advised Sen. Barack Obama on economic policy . He urged Congress to pass the $ 700 billion bailout bill . He bought stakes in Goldman Sachs and General Electric .

He wrote an op-ed piece in the New York Times saying he 's buying stock in American companies now because he believes they will do well in the long run , citing as his rule : `` Be greedy when others are fearful . ''

Buffett 's name came up in the second presidential debate when the candidates agreed he 'd be a good choice for treasury secretary . His fortune was estimated at $ 62 billion by Forbes in March .

Alice Schroeder got Buffett 's cooperation in writing her new book , `` The Snowball : Warren Buffett and the Business of Life '' -LRB- Bantam Books -RRB- . Schroeder , who worked on Wall Street as an insurance industry analyst , met Buffett 10 years ago when his company , Berkshire Hathaway , bought a big insurance company .

Schroeder says she suggested he write a book about his life , and the 78-year-old Buffett turned the tables , urging her to do it instead . Schroeder estimates she spent about 2,000 hours with Buffett and interviewed 250 people for the book . Now on a tour to promote her book , Schroeder is in a unique position to speak about Buffett at a time when many media outlets are seeking his views .

`` I have about 300 hours of recorded interviews and the rest of the time I observed him , I watched him make decisions and talk on the phone , went through files . I got to sit in his office for weeks , I ate steaks with him , '' says Schroeder , who 's 51 . `` If it ever said moo , he 'll pretty much eat it . He likes his steaks bloody rare and hanging off the plate , they 're so big . ''

CNN : Why are people so interested in Warren Buffett ?

Schroeder : I think he 's transcended business to become a national figure because of people 's trust in him as a symbol of stability and a symbol of someone who knows how to manage risk and avoid catastrophe and of how to run a business on principles .

CNN : Is there any realistic possibility of him taking a government position ?

Schroeder : No , none . What he really likes to do is run Berkshire Hathaway , and he 's not going to let anything take him away from that . He 's also not going to let anyone spend his day filled up with meetings or schedule his time , he 's too independent .

CNN : You make clear that in the 1990s tech boom , Wall Street turned away from Buffett and there was some criticism of him . Do you think that now , because of the market downturn , people will look to him more to set a standard of how the market operates ?

Schroeder : I think it 's fair to say that throughout his career , every time there 's been a bubble and it 's burst , his reputation has grown . That happened in the 1960s , when the bubble burst in the 1970s , it happened again after 1987 . It happened again after the savings and loan crisis . ... It happened again after the Internet bubble and it 's happening now .

CNN : It does n't seem to have had a lasting effect , since we keep going back into another boom period or bubble .

Schroeder : He would say that human nature does n't change , and that fear and greed are always the two drivers of the market . And there are people who listen when he gives learnings , but that the market will always be ruled by cycles driven by fear and greed .

CNN : Have you talked to him about the current market turmoil ?

Schroeder : Last spring , when Bear Stearns was being taken over by J.P. Morgan ... he talked about the dominoes falling , and how , if that happened , the government could face some very unpleasant choices and have to take drastic measures . With hindsight it looks really prescient . In 2002 , he talked about derivatives as financial weapons of mass destruction .

More recently , his observation was that there was a lot of anger and denial at first about what was going on , and that people were not quite grasping the gravity of the situation and how quickly and dramatically they needed to move .

He always says , do n't sell into a panic , do n't let the fear and the emotions of the market change how you feel . If you own good stocks in good companies or you own an index of the markets , and you see it getting cheaper , that 's a reason to be happy , not to panic and sell . ... The idea is buy low , sell high -- not buy high , sell low .

He understands the factors that are burdening the country , the federal deficit , the consumer debt , the infrastructure spending that we 're going to have to do , but he has a belief in American ingenuity which over the long term has enabled our country to solve problems that seemed insurmountable in the past . For example , in the 1970s , it looked like the country could not ever dig its way out of the mess . So he does have a faith in the long-term prospects of the country .

CNN : Is he a gambler ?

Schroeder : No , he 's a handicapper -- big difference . A handicapper is somebody who understands odds-making . A gambler is somebody who bets but may not even understand the odds . Warren believes in a margin of safety , he does n't bet unless the odds are overwhelmingly in his favor . When he goes to Vegas he does not gamble , he goes to see the shows .

CNN : What are his flaws ?

Schroeder : He is somebody who can be very tough in business and very impersonal , including with people he likes . And in personal relationships , he negotiates as if it were a business relationship

When he was putting Berkshire Hathaway together , as -LSB- his business partner -RSB- Charlie Munger puts it , he was an implacable acquirer . The book refers to him , in my words , as a great white shark , and the book describes the battle between his avarice and his higher principles . At times , his avarice won .

And over his lifetime , it 's been essentially a progress during which his higher principles have increasingly had the upper hand . But when he was in junior high , he was a shoplifter . He was a juvenile delinquent . He sold his sister 's bicycle . It 's been pretty much uphill from there , but it has n't been a straight line .

CNN : In his adult life , was there a time when his avarice won out over higher principles ?

Schroeder : Absolutely , he 's made investments that he should n't have made , for example , when he invested in Salomon . He was criticizing Wall Street and saying if you want to make a lot of money , hold your nose and go to Wall Street , and at the same time he was already there . Berkshire owned $ 700 million of convertible preferred -LSB- stock -RSB- in a major Wall Street bank . And he was sort of mentally distancing himself from a business that he was invested in .

That kind of separation is something that 's very hard to maintain . And in the end , he had to become interim chairman of Salomon to rescue the firm . Psychologically , he was trying to distance himself from it because the two sides of him were at war .

CNN : Is he still critical of Wall Street ?

Schroeder : You 've got an economy in which financial intermediaries who do n't add anything to the economy ... have in the past two decades stripped off huge amounts of fees , particularly buyout funds , and hedge funds and funds of funds , and he 's very , very critical of the amount of fees that have been taken out .

He has no problem with executive pay when it 's related to performance . He thinks in most cases executives are being paid to sit in a chair whether they perform or not . And he 's pointed out that these people are not like major league baseball players , who get recruited away by other teams . When CEOs get fired and they get these golden parachutes , you do n't normally see them winding up somewhere else , right ?

So they 're getting paid these huge amounts of money as an incentive to stay and then they get paid the consolation prize when they get fired . The pay is always getting ratcheted upward , they 're getting paid to incent them to stay and they 're getting paid to console them when they leave , no matter what the shareholders are getting . It 's not aligned with anything the shareholders get , that really bothers him .

CNN : What would he say about coping with an economic downturn ?

Schroeder : That people should think for the long run and make their personal decisions for the long run and build a margin of safety into their lives as best they can .

Think about what could go wrong . Do n't assume the best-case scenario . If you 've got debts , your first thought should be how to pay them off , and negotiate with creditors if you 're struggling , because they 'll usually be flexible . And be realistic about what you can afford , because having a financial cushion means you can sleep at night , and that 's worth more than a big-screen TV .

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Alice Schroeder : Buffett is viewed as a symbol of stability and safety

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Buffett 's career is a battle between avarice and higher principles , she says

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Schroeder : Buffett 's critical of high fees and high executive pay on Wall Street

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Buffett has faith in American ingenuity to overcome challenges , she says